A surface working machine, such as a grader or plough, employs a large generally horizontal blade to work the surface as needed. The large blade is generally comprised of a moldboard having detachably mounted on the lower edge thereof a blade (shown for example in FIG. 1 or 2) which sustains the principle wear and abrasion. The blade may be any type of surface working blade including a cutting edge, serrated edge, etc, and is typically the result of the end to end connection of a plurality of blade segments. Eventually, the overall blade or one or more blade segments becomes worn and must be replaced. In case of local damage, the entire blade segment must be replaced.
One industry tendency has been to make the blade segments as long as possible to reinforce the thinner moldboard. The size and weight of the blade segments with installed tools has increased and is very difficult to manhandle. Changing a set of segments is a two-man operation.
The idea of shortening the individual blade segments that make up the blade has been explored and results in moldboard deterioration. The moldboard of the machine is thinner than the blade and blade segments. In previous attempts, when multiple shorter sections of the blade segments were used, it would reduce the strength of the assembly in the area where the shorter segments were butting together. This problem is stipulated, for example, in Canadian patent 940298.
It has also been observed, that even when longer segments are used in an effort to reduce the weakening of the overall blade, the local join region of the moldboard associated to the gap between adjacent segments, allowed for fine material particles to flow between the segments and washout or erode the moldboard.
Shortening the segments to allow for easier manhandling results in an increase in the number of joins and therefore an increase in the washout or erosion of the moldboard. Shortening the segments also causes problems in properly positioning an adequate number of fasteners onto the shorter segment while still using available connection holes on the moldboard.
In the current state of the art, significant amount of wear is observed at the front lower face of the blade. Presently, this area may be protected with wear strips welded on the front lower face of the blade. However, this solution adds additional weight and cost to the tool carrier blade. Also, replacement of the wear strip can only be done in a shop with adequate welding equipment.
An additional problem associated with the current state of the art blade assemblies relates to blade assemblies including a tool carrier blade wherein a plurality of tool bits are connected to the blade. Wear is observed under the tool flange and is not reduced through the use of a wear strip as outlined above. Further, in operation, when a portion of the blade is not in contact with the ground, it is commonly found that the strength of the tool spring clip is not sufficient to hold the tool in place. In a road maintenance operation, typically the end-section of the blade hangs over the edge of the road and tools that are suspended may be dislodged and fall off.
A need therefore exists to provide a blade segment and blade assembly therewith which overcomes or mitigates one of the deficiencies outlined above or that is observed in the industry. A need further exists to provide a tool retaining clip which overcomes or mitigates one of the deficiencies outlined above or that is observed in the industry.